• From: London
  • Registered: 2007-05-04
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Topic: Digicheck channel status display Approximated s/f

I notice the value is fluctuating between 47.93 and 48.12 Khz when playing back dvd what that does that mean to audio, does that mean the original master clock is not accurate. Is it meant to do that?

I know it's crazy to compare to DCS verona says accuracy typically 0.1ppm, guaranteed less than 1ppm especially as it is ?3999!!!

http://www.dcsltd.co.uk/datasheets_audi … verona.pdf

So at 48khz the dcs will be 48000 +/- 0.048 Hz ?

And my DVD is 48000 +/- 100 Hz ???

So that is DCs verona at +/- 0.02ns clock stability at 48khz

and DVD at +/- 43ns clock stability?

So if I got a RME card with steadyclock that would fix the clock stability to +/- 2ns of whatever the clock that created the file?


Approximated s/f

DIGICheck allows to measure the real sample rate with an accuracy of ? 100 Hz. This is a very useful addition to the Sample Frequency display in the Settings dialog.

Most RME systems show (and measure) the sample frequency within a +/- 4% range, sufficient to detect the clock used when connecting other devices.

But if you want to check slow speed deviations from incompatible or defective equipment, or the behaviour when syncing several devices (especially when controlled by timecode SMPTE), the value in Approximated s/f gives a useful indication what's realy happening in the digital domain.

RME RPM + PCI, SL1200, Nad c350 , Dynaudio Audience 52, Ableton, Traktor. Dell 9200 E6600 XP Home
  • From: London
  • Registered: 2007-05-04
  • Posts: 95

Re: Digicheck channel status display Approximated s/f

Then when I play a sine wave generated in Soundforge the Approximated s/f(slow) is exactly 44.10 khz.

RME RPM + PCI, SL1200, Nad c350 , Dynaudio Audience 52, Ableton, Traktor. Dell 9200 E6600 XP Home

3 Reply by shudupanddance (edited by shudupanddance 2007-05-19 13:39:42)

  • From: London
  • Registered: 2007-05-04
  • Posts: 95

Re: Digicheck channel status display Approximated s/f

Right...

In the uk they broadcast the time and date.

The MSF transmission from Anthorn (latitude 54? 54' N, longitude 3? 16' W) is the principal means of disseminating the UK national standards of time and frequency which are maintained by the National Physical Laboratory. The effective monopole radiated power is 15 kW and the antenna is substantially omnidirectional. The signal strength is greater than 10 mV/m at 100 km and greater than 100 ?V/m at 1000 km from the transmitter. The signal is widely used in northern and western Europe. The carrier frequency is maintained at 60 kHz to within 2 parts in 10-12.

If the carrier frequency is that accurate why can it not be used by wordclock generator?


http://www.npl.co.uk/time/msf/ctm001v05.pdf

RME RPM + PCI, SL1200, Nad c350 , Dynaudio Audience 52, Ableton, Traktor. Dell 9200 E6600 XP Home

4 Reply by MC

  • MC
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Re: Digicheck channel status display Approximated s/f

shudupanddance wrote:

I notice the value is fluctuating between 47.93 and 48.12 Khz when playing back dvd what that does that mean to audio, does that mean the original master clock is not accurate. Is it meant to do that?

Yes. This is a software routine that can be disturbed by external events. Then the readout will fluctuate a bit. Maybe we add a flux compensator one day...

Regards
Matthias Carstens
RME

MC's Website

5 Reply by shudupanddance (edited by shudupanddance 2007-05-21 11:56:20)

  • From: London
  • Registered: 2007-05-04
  • Posts: 95

Re: Digicheck channel status display Approximated s/f

smile Matthias I assume you were talking about one of these... http://en.wikipedia.org/wiki/Flux_capacitor

Maybe soon there will be one of these inside wordclock. http://tf.nist.gov/ofm/smallclock/index.htm

RME RPM + PCI, SL1200, Nad c350 , Dynaudio Audience 52, Ableton, Traktor. Dell 9200 E6600 XP Home
  • From: London
  • Registered: 2007-05-04
  • Posts: 95

Re: Digicheck channel status display Approximated s/f

Matthais, is a flux compensator a real thing? I assumed you were joking.

RME RPM + PCI, SL1200, Nad c350 , Dynaudio Audience 52, Ableton, Traktor. Dell 9200 E6600 XP Home
  • kws
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Re: Digicheck channel status display Approximated s/f

shudupanddance wrote:

Matthais, is a flux compensator a real thing? I assumed you were joking.

From the Wikipedia article about Flux Capacitor:
In the German-dubbed version [of Back to the Future], the device was once again mistranslated and called the "Fluxkompensator" ("Flux compensator"). The correct German translation for the word capacitor, however, would be "Kondensator".

8 Reply by MC

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Re: Digicheck channel status display Approximated s/f

kws wrote:
shudupanddance wrote:

Matthais, is a flux compensator a real thing? I assumed you were joking.

From the Wikipedia article about Flux Capacitor:
In the German-dubbed version [of Back to the Future], the device was once again mistranslated and called the "Fluxkompensator" ("Flux compensator"). The correct German translation for the word capacitor, however, would be "Kondensator".

Didn't know that :-)

But the movie translators were right as Flux Kompensator (flux compensating device) sounds much more impressive in german ;-)

Regards
Matthias Carstens
RME

MC's Website